Page 243 - Designing Sociable Robots

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224 Chapter 12

prior experience with a variety of interactive toys. Each subject interacted with the robot
for twenty to thirty minutes. All exchanges were video recorded for further analysis.
For the purposes of this chapter, I analyzed the video for evidence of social amplifica-
tion. Namely, did people read Kismet’s cues and did they respond to them in a manner
that benefited the robot’s perceptual processing or its behavior? I found several classes of
interactions where the robot displayed social cues and successfully regulated the exchange.

Establishing a Personal Space
The strongest evidence of social amplification was apparent in cases where people came
within very close proximity of Kismet. In numerous instances the subjects would bring
their face very close to the robot’s face. The robot would withdraw, shrinking backwards,
perhaps with an annoyed expression on its face. In some cases the robot would also issue
a vocalization with an expression of disgust. In one instance, the subject accidentally came
too close and the robot withdrew without exhibiting any signs of annoyance. The subject
immediately queried, “Am I too close to you? I can back up,” and moved back to put
a bit more space between himself and the robot. In another instance, a different subject
intentionally put his face very close to the robot’s face to explore the response. The robot
withdrew while displaying full annoyance in both face and voice. The subject immediately
pushed backwards, rolling the chair across the floor to put about an additional three feet
between himself and the robot, and promptly apologized to the robot. (Similar events can
be viewed on the sixth CD-ROM demonstration, “Visual Behavior.”)
Overall, across different subjects, the robot successfully established a personal space.
As discussed in the previous section, this benefits the robot’s visual processing by keeping
people at a distance where the visual system can detect eyes more robustly. This behav-
ioral response was added to the robot’s repertoire because previous interactions with naive
subjects illustrated the robot was not granted any personal space. This can be attributed to
“baby movements” where people tend to get extremely close to infants, for instance.

Luring People to a Good Interaction Distance
People seem responsive to Kismet’s calling behavior. When a person is close enough for
the robot to perceive his/her presense, but too far away for face-to-face exchange, the robot
issues this social display to bring the person closer (see chapter 10). The most distinguishing
features of the display are craning the neck forward in the direction of the person, wiggling
the ears with large amplitude, and vocalizing with an excited affect. The function of the
display is to lure people into an interaction distance that benefits the vision system. This
behavior is not often witnessed as most subjects simply pull up a chair in front of the robot
and remain seated at a typical face-to-face interaction distance (one example can be viewed
on the fifth CD-ROM demonstration, “Social Amplification”).